Method of making valves



April 5, 1938. J. BUGATTI METHOD OF MAKING VALVES 2 Sheets-Sheet 1Original Filed May 23, 1935 A7 a 4 j April 5, 1938. J T 2,113,316

METHOD OF MAKING VALVES Original Filed May 23, 1935 2 Sheets-Sheet 2 I.mm V 7 Wha'uw f il MM Patented Apr. 5, 1938 METHOD OF MAKING VALVESJean Bugatti, Molsheim, France Original application May 23, 1935, SerialNo. 23,100, now Patent No. 2,072,615, dated March 2, 1937. 15, 1936,Serial No. 90,813. 25, 1934 6 Claims.

The present invention which is a division of the U. S. patentapplication Ser. No. 23,100, filed May 23, 1935, Patent Number2,072,615, issued. March 2, 1937, relates to valves of the mushroomtype, and its object is to provide an improved valve of this type.

The essential feature of the present invention consists in giving thevalve head a laminated structure, that is to say composed of a pluralityof laminas superposed in adjacent relation and which, individually,possess a certain elasticity or a certain freedom of movement while theassembly of the whole possesses the required rigidity.

Owing to the elasticity thus obtained, the valve head is always appliedin a fiuidtight manner against its seat, even under unfavorablecondition, that is to say, for instance, when this seat is not uniformlyworn or is subjected locally to expansions different from the expansionsin other points. Furthermore, when the valve is utilized in an engineoperated through a fluid at a high temperature, for instance an internalcombustion engine, the cooling of the valve according to the presentinvention is considerably improved because it has been found that mostof the heat transmitted to the valve head is evacuate-d through theseat, and in the present case there is an intimate contact between saidseat and the valve head over the whole periphery thereof.

Since the valve head is elastic, the sudden shock that occurs when thevalve is closed is partly absorbed since the energy (kinetic force) ofthe pieces in movement is partly absorbed by the elastic deformation ofsaid valve head. Therefore the hammering of the seat by the valve isavoided, which is important for the good preservation of these delicatepieces. As the valve closes Without any important shock, its working ismuch less noisy than that of ordinary valves.

The arrangement according to the present invention is particularly welladapted to the case of double head valves, that is to say of valvesprovided, on a common stem, with two heads or discs located at a certaindistance from each other and intended to be applied each against itsrespective seat. Valves of this type are often employed with highpressure fluids because they can be balanced with reference to theaction of the pressure thereon and they are accordingly easier tocontrol. Now, such valves work generally in a medium in which variable,and most often very high, temperatures exist. They may Divided and thisapplication July In France May therefore dilate in a nonuniform manneror they may not be applied accurately on the corresponding seats whenthese various elements expandi Furthermore, as the valve discs and thecorresponding seats are machined separately, small differences oftenexist between the distance between the seats and the distance'betweenthe valve discs. Consequently, it is always diflicult to ensure and tomaintain fluidtightness between valve discs of this kind andtheir'respective seats.

In this case, the present invention consists essentially, in order toobviate the drawbacks inherent in known valves of this kind, in makingat least one of the valve discs elastic, as above explained, so that itcan compensate for the slight axial difference in the distance betweenthe seats.

In a preferred embodiment of the invention, the valve head is divided,in a direction at right angles to the axis of the valve stem, into arigid portion and an elastic portion, which, at least in its peripheralzone where it is to bear against the seat, is at a very small distancefrom this rigid portion, the latter acting as an abutment for saidelastic portion. I

Another feature of the present invention consists in providing a doublevalve of the type above referred to arranged to permit a certainrelative displacement of the valve heads with respect to heads with eachother may be reduced in order to render this portion of the stemelastic. But this feature cannot be employed in many cases. This is dueto the fact that the distance between the valve heads is necessarily inrelation with their diameters and it is necessary to leave a suflicientcross section of the valve stem for keeping the end valve head in properaxial position.

In a preferred embodiment of the invention, each of the valve heads isprovided with a distinct stem and the stem of the end valve head isengaged into the hollow stem of the other valve head and is fixed at thebottom of said hollow stem through any suitable means (by screwing,keying, etc). With this arrangement, the end valve head can be providedwith a sufficiently long and flexible stem. It is preferably madeelastic in the manner above stated. Therefore,its deformabilitycompensates for the lack of perpendicularity of itsdisplacements withre- '55 spect to the axis of the other valve head. Besides this defectis of very little importance due to the great distance of the end valvehead to the point where the stem thereof is fixed.

Other features of the present invention will result from the followingdetailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafterdescribed with reference to the accompanying drawings, given merely byway of example, and in which:

Fig. 1 is an elevational view, partly in axial section, of a firstembodiment of a valve according to the present invention;

Fig. 2 is a view similar to Fig. 1 and corresponding to anotherembodiment;

Fig. 3 is an elevational View, partly in section, of a double head valveaccording to the present invention;

Figs. 4 and 5 are partial sectional views illustrating the method ofmanufacturing the elastic valve head of Fig. 3, said valve head beingshown at two different times of its manufacture;

Fig. 6 is a longitudinal sectional view of a valve provided with twovalve heads connected together through a flexible stem according to thepresent invention.

In the embodiments of Figs. 1 and 2, each valve head includes threeelastic laminas I, 2 and 3, obtained for instance by making nicks in themetal at 4 and 5. In the embodiment of Fig. 1, laminas l and 3 have beencurved toward each other at their periphery so that the valve head hasthe usual shape. The intermediate lamina 2, which is shorter than theother ones, is provided with a substantially conical surface 6. Theintervals between these laminas and the thicknesses thereof are suchthat, if lamina 3 is deflected at its periphery, it comes to bearagainst lamina 2 and then the whole is applied, through the peripheraledge of 3 against the third lamina l. Of course, the valve could be sodevised that part 3 first comes into contact with part I, and then withpart 2, or with both simultaneously. In any case, it will be readilyunderstood that the elasticity of the valve head is gradually variable.of course, it is necessary that the deflection of these three laminas I,2, 3, working in parallel should be limited in such manner that thevalve head can always perform its function, which is to stop the holelimited by its seat.

In the embodiment shown by Fig. 2, the three laminas are made ofsubstantially the same external diameter, and in this embodiment alsothe elasticity of the composite valve head is gradually variable asabove explained.

Of course it should be well understood that the invention is not in anyway limited to the embodiment just above described. It can be applied aswell to explosion engines as to combustion engines, to steam engines, tocompressors, and so on.

The invention can obviously be applied to the case of a valve the stemof which carries a plurality of valve heads, and in this case all or apart of these valve heads may be made according to the invention asabove stated.

Figs. 3 to 6 relate to the case of double head valves. In the embodimentof Figs. 3 to 5, the valve, which includes a stem 7 and two valve heads8 and 9, controls the inflow of fluid from a chamber l into anotherchamber I I. The valve element 9 includes a rigid portion 12 and aflexible portion 13. I have shown at IS a removable plug which permitsto examine the valve system and to remove it in case of need.

When machining the element 9 of the valve, I first leave a very thickdisc. Then this disc is divided into two portions I2 and 13 by providingan annular groove [4 (Fig. 4) of a suitable width and extending radiallyas far as the diameter of the rod or stem. Finally the elastic portionI3 is bent in the hot state in the direction of the rigid portion, asmall play being provided at l (Fig. 5) so as to permit the elasticcompensation above referred to. Portion I3 has been thinned down in thecentral portion so as to obtain the required elasticity.

In the embodiment shown by Fig. 6, the stem I 8 of the elastic valvehead I! is provided with a cylindrical bore I9 in the bottom of whichthe stem 2| of the other valve head 22 is fixed, for instance byscrewing at 20. A sufficient play is provided between the inner wall ofbore l9 and stem 2|, in such manner as to permit this last mentionedstem to be deformed, for instance as shown in dotted lines. Suchdeformations permit the two valve heads I! and 22 to be applied againsttheir seats in a satisfactory manner even when said valve heads or saidseats are not quite exactly parallel. As shown in the drawings, valvehead 22 is elastic, which permits a correct application of this valvehead against its seat in spite of the lack of perpendicularity of saidvalve head with respect to axis X-Y when the valve is deformed as shownby the dotted lines.

While I have, in the above description, described what I deem to bepractical and efilcient embodiments of the present invention, it shouldbe well understood that I do not Wish to be limited thereto as theremight be changes made in the arrangement, disposition and form of theparts without departing from the principle of the present invention ascomprehended within the scope of the accompanying claims.

What I claim is:

1. In the manufacture of an elastic valve head, the steps which consistin machining a peripheral groove into a disc-like blank of elastic metalto divide the latter into two spaced apart flanges projectingsubstantially radially from an integral center part, and thinning downone of the said flanges to render it flexible.

2. In the manufacture of a valve, the steps which consist in formingwith an elastic metal a blank including a thick head and a stem integralwith said head, projecting centrally therefrom; machining a peripheralgroove into said head in a plane substantially at right angles with saidstem so as to divide the head into two spaced apart flanges integralwith a common center part; and thinning down one of the said flanges torender it flexible.

3. In the manufacture of valves, the steps consisting in forming aperipheral groove into a head blank made of an elastic metal so as toproduce two flanges spaced apart from one another but still attachedintegrally to a common center, thinning down one of the said flanges torender it flexible, and hot drawing the peripheral portions of saidflanges near to one another.

4. In the manufacture of valves, the steps consisting in forming aperipheral groove into a head blank made of an elastic metal so as toproduce two flanges spaced apart from one another but still attachedintegrally to a common center, and thinning down the center portion inone of the said flanges to render it flexible.

5. A method for the manufacture of a valve which comprises forming arelatively thick disclike blank on a valve stem, cutting an annular Widegroove into said disc from the edge thereof towards the center part ofthe disc to divide it into two rigid flanges spaced apart from oneanother but attached integrally to a common center part, thinning downthe center part of one of the flanges to render it flexible, heatingsaid thinned flange and bending the thinned flange while hot, to drawits peripheral portion towards the peripheral portion of the otherflange.

6. A method for the manufacture of an elastic form an elastic valve headhaving its peripheral 10 portion thinner than its central portion.

JEAN BUGATTI.

